A lot of semi-automatic rifles look like military weapons, and in many cases they are. But most types of semi-automatic AR-15 rifles — like the one the Broward Sheriff’s Office said was used to massacre 17 people at Marjory Stoneman Douglas High School Wednesday afternoon — are legal for civilian use across the United States. In Florida, almost any adult can buy a rifle so long as they are not a convicted felon.
Another exception: those with medical marijuana cards.
Most guns used in mass shootings across the United States were legally obtained — sometimes by the individual, or they were taken from a family member with a permit.
“AR-15s are designed to kill multiple enemy combatants at once,” said Frank Smyth, weapons expert and founder of GJS, an organization that trains journalists for combat reporting. “But of course in the hands of an active shooter or an individual that was targeting civilians, it’s a tactical weapon. It enables them to target multiple people in a quick period of time.”
It is still unknown whether the AR-15 used at Stoneman Douglas High Wednesday belonged to Nikolas Cruz, the suspect now in the custody of law enforcement. Cruz is not listed as holding a weapons license through the Florida Department of Agriculture and Consumer Services, the government agency tasked with monitoring gun owners and concealed carry licenses. However, witnesses at the scene told the Miami Herald that Cruz had previously talked about having guns at home and using them.
Wednesday’s incident was the 30th mass shooting of 2018, according to the Gun Violence Archive, an organization that aggregates gun violence data. It was also the deadliest. And while semi-automatic handguns still account for the vast majority of weapons used in mass shootings across the United States, semi-automatic rifles are increasingly common weapons of choice.
The shooter in Las Vegas, had 23 weapons stashed in his hotel room, including several semi-automatic AR-15s like the one he used to shoot out the window down at the crowd. Smyth said the shooter at the Pulse nightclub in Orlando used a semi-automatic MCX that was marketed as a “next-generation” AR-15.
“AR-15” is used as a generic term for a broad range of semi-automatic rifles, designed to be tactical versions of the original automatic M16 military rifle. AR-15 weapons are often used by SWAT teams and other tactical teams during, often close-range, operations. That design change, from automatic to semi-automatic, is what makes an AR-15 legal for civilian sale.
AR-15 style weapons are designed and manufactured by many different companies. And some models, like the Colt M4 carbine, can shoot semi-automatically as well as in three round bursts. A bump stock, the stock replacement now infamous for its role in increasing casualties in last year’s Las Vegas shooting, can make an AR-15 into a crude version of an automatic weapon.
Sound recordings from inside the school Wednesday indicated that the weapon in question was on a semi-automatic setting, according to Smyth, who heard about 12 shots in a video posted to Twitter. “He was not using a bump stock,” said Smyth. “With a semi-automatic you squeeze the trigger and it automatically reloads.”
Generally speaking, an AR-15 shoots small caliber rifle rounds with gunpowder cartridges the size of a stubby finger. “It’s a relatively small bullet. But it’s a high-power round with a relatively large amount of gunpowder behind it,” Smyth said.
The rounds are lighter than other larger rifle rounds, so they tumble on impact with a target, according to independent weapons expert Michael Limatola. A light bullet will zig-zag through flesh, and usually leaves a gaping exit-wound.
This post has been updated to clarify who can buy a rifle in Florida.